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A Conversation on Bioethics with Linda Sonntag, PhD
By Mari Hoffman, Genetics & Genomics ‘21
Author’s Note: I was interested in interviewing Dr. Linda Sonntag because of her time and dedication spent in the biotechnology field. She has been involved in multiple biotechnology companies as the Chief Executive Officer and participating as a board member. The multitude and diversity of her experiences with different companies and projects have encouraged her to get involved with bioethics. She has been a leader in bioethics and has started many of the bioethical conversations that are still being discussed today. In that capacity, she has formed multiple bioethics committees, including the very first. I was very honored to be able to interview Dr. Sonntag and ask her some of my own questions revolving around bioethics in the past and modern development of biotechnology.
This interview has been lightly edited for clarity and brevity.
Mari Hoffman: To start off, if you would like to give a brief introduction on who you are and your background.
Dr. Linda Sonntag: My name is Linda Sonntag, and I was born, raised, and educated in South Africa. I came to the United States in 1980 and completed my post-doctoral studies at UCSF with Herbert Boyer, the founder of Genentech. I quickly realized that I was not cut out for academia in this country. I come from being a very big fish in a very small pond and now I was a Mino in the ocean. I had to find a different way of using my education and I decided to go into industry, which was right at the beginning of the formation of biotechnology.
MH: Since you entered the field of biotechnology when it was still relatively new, when do you first remember a conversation on bioethics taking place and how has that conversation changed with the increasingly advancing technology and scientific capabilities that we have today?
LS: The very first conversation on bioethics took place before my involvement. I think it took place around 1976 at a seminar that was led by David Baltimore, after recombinant DNA and genetic engineering were first discovered. People were concerned about what could be done with biotechnology (a term only coined in the early 1980’s) and a public conversation on bioethics up until this point had not occurred. The technology was way ahead of any conversations or agreement on how to proceed to use it for the common good and not ill. To address the concerns on the ethical issues related to recombinant DNA, a conference was organized to discuss the ethics at Asilomar, in Northern California. A moratorium was placed on all genetic engineering for academic research until the scientist could agree on what was ethical or not. The moratorium lasted several years. During this time, a number of research areas were declared ethical and others not, and the organizers also played a significant role in establishing rules and regulations as well as the creation of multiple regulatory bodies to govern the use of recombinant DNA. At that time, the scientists were able to restart their research in a robust way.
MH: What was your first direct experience with starting a conversation on bioethics?
LS: The first company I worked with was called Agrigenetics and it was the very first agricultural biotechnology company. At the time, no regulations were in place by any federal agency to regulate genetically modified foods (GMA). The very first conversation that I had around bioethics was around whether or not the agricultural industry should be regulated. I was the lone voice who believed it should be regulated. I was very concerned that if there were no regulations, people would be very frightened by the products we wanted to commercialize if we were successful. They might view us as creating monsters that could escape into the environment. Although I had my concerns, for expediency’s sake, the industry leaders as a whole decided against being regulated because regulation adds significant costs and delays the time to reach the market.
The very first experiment that went into the field was in Davis, CA, associated with a company that was founded by academic scientists at UC Davis. It was for a strawberry plant that had been engineered to have an anti-freezing gene derived from fish inserted into its DNA so that strawberries would not freeze and the crop would not be destroyed when there was frost. When the GMO plants were planted, local citizens in the area protested and rioted by breaking down the greenhouses and destroying the crops. That product never reached the market.
Agricultural biotechnology eventually took off, but in a highly regulated way. You can still see the stigma today that GMO plants and seeds hold; people remain afraid of them and the business models around how they are sold.
MH: How did that experience lead to you making a change in a company’s regulations?
LS: My next involvement was a very interesting one. Around 1985, I joined a startup where we were the first to practice precision medicine and use it to create a preventive medicine program that was designed for a circumscribed group of individuals. Historically, prevention has always been in the domain of government and consequently had been very costly to implement since governments could not be seen to discriminate and therefore all newborns were being tested for those diseases that were preventable, whether they were at risk or not.
I went around the country and licensed many genes that had been identified in academic labs that were linked to preventable diseases. They had the potential to be powerful predictors to identify who was at risk for certain diseases. I eventually licensed about 50 different genetic markers that could be used to identify individuals’ predispositions for developing a disease that was preventable. I was only interested in licensing genetic markers for diseases that had an environmental and/or behavioral component to them and that a patient could do something to change the outcome of the disease. After licensing these technologies, we created the very first artificial intelligence system which allowed us to circumscribe who was at risk. To test out the system we were involved with a large telephone company in Washington, DC who opted to offer our test to their employees. It quickly became very evident that with no rules in place, individuals were not protected from being discriminated against by their employers or insurance companies because they had a genetic profile that identified them as being at risk of developing diseases that could result in considerable healthcare costs or disruption to an individual’s productivity. To think through and address these issues, I created the very first bioethics committee, dedicated exclusively to problem solve and develop systems to protect individuals from discrimination. To overcome these issues, we were successfully able to identify individuals, and only we held the key to their identity and were able to preserve the patient’s anonymity from their employers and insurers. They could now get access to educational programs and support without their identity being exposed. That was the very first time that a bioethics committee was created as an institutional entity that made decisions about how businesses would be run in a more mindful and ethical manner.
MH: That is very interesting. Would you say with ancestry tests like 23andMe where you are provided an option to give your name overrides the anonymity of genetic tests that you discussed?
LS: Absolutely. What we have discovered now is even if that data is anonymized, there are ways to deconstruct and identify individuals.
MH: It is very interesting that this conversation on data privacy that you started years ago is still a prevalent issue today. Are there any set laws that are currently in place today to provide protections?
LS: Laws do exist to protect genetic information from being used prejudicially, but if an individual gets refused insurance it is really hard to find out why they have been refused. If an employer has accessed that data and uses it prejudicially, for one to have any recourse, you have to prove that it was based on their knowledge of that genetic information, which is very difficult to prove.
The one law that is unfortunately currently at risk is the protections that come from the Affordable Care Act (ACA). The ACA forbids insurance companies from using pre-existing conditions to deny an individual any insurance. Due to COVID-19 and the Trump Administration’s attempt to end the ACA, a multitude of individuals who have lost their health insurance this past year due to the pandemic are now at risk of no longer being able to buy insurance that covers pre-existing conditions. All the sequelae and multitudes of long term health consequences of COVID-19 could be excluded from coverage by anyone who has lost their job as a consequence of this pandemic of epic proportions. A genetic predisposition might be included as a pre-existing condition, which might disqualify an individual for insurance. As long as the ACA is the law, nobody can be denied insurance for those reasons. Although there are these laws that exist, there are still issues around them and how to enforce them.
MH: Have there been any other experiences that you have that have led you to build a bioethics committee?
LS: The third time that I got involved in bioethics and formed a committee was when I was running a company called SyStemix, the very first stem cell company. We were using fetal tissue in our experiments which was a topic that has been controversial under Trump and prior to that during the George W. Bush administration. We were one of the first commercial companies that was openly admitting to using fetal tissue in our experiments. We knew that this might be highly controversial, so once again, I assembled a bioethics committee to opine on what we would face and how best to deal with the issues. Our committee actually included a Catholic Bishop to be a part of the conversation and eventually concluded that since we were not in any way women to choose abortion and since we were not paying for the tissue, the abortuses were simply being disposed of with no potential to benefit humankind. Even the Bishop agreed that using fetal tissue for the benefit of humankind was a worthwhile endeavor, as opposed to throwing the embryos away.
Just this last year, Trump dismantled every single research project funded by the United States government that used fetal tissue in any way, thereby squandering hundreds of millions, if not billions of dollars worth of experiments by having all that research come to a screeching halt.
Our company was founded on the use of a SCID-hu mouse model where any tissue from any organisms can be transplanted into the mouse since the mouse did not have an immune system of its own. It could not recognize the donor tissue as foreign and hence would not reject it. Few adult organs are capable of regeneration, whereas virtually every fetal tissue has applicability in these valuable experiments. This mouse model became the gold standard for all research on the etiology of human diseases and the potential ways to treat them.
In our case we were able to use it for AIDS and HIV research. It was the first time that we could actually create a fully functional human immune system in a mouse and infect it with HIV, to determine if different drugs could potentially cure HIV and AIDS. AZT, the very first approved HIV-antiviral drug was discovered to be effective in humans by using the SCID-hu mouse model around 1990. AZT is a pro-drug, and the only other organism that can convert it from a prodrug to an active drug is chimpanzees. By using this mouse model, it was no longer necessary to infect chimpanzees with HIV to study the disease. This year, unfortunately, for political reasons, all experiments that were using this gold standard mouse model for studying many human diseases came to a halt because President Trump decided that fetal tissue could not be used in any circumstance in any government funded research programs, for purely political reasons.
MH: What do you think are some of the most current pressing bioethical issues?
LS: The other discussion that is very current, but I have mixed feelings on is about vaccines for COVID-19. COVID-19 trials are blinded and are conducted by splitting cohorts of individuals in a control arm and a treatment group, without the researchers or participants knowing which group is receiving the vaccine. Now that the experiments are unblinded and we can see that the vaccine is highly efficacious, the question becomes whether or not people in the control arm should be vaccinated. If they get the vaccine, it truncates our ability to see for example the longevity of the protection provided by the vaccine or long-term side effects by no longer being able to track the control group. So, what to do? The way the health care community is leaning is that the control group has to get the vaccine to protect them and then we have to figure out other ways to understand the longevity and side effects of vaccination. This is an ongoing discussion at the FDA and the NIH in order to make these important decisions around how to continue the clinical trials. Also, once the first vaccine is approved, how do you get other vaccines tested if there is already a vaccine available? There are a lot of ethical questions to consider regarding these issues.
MH: There is a lot of stigma about taking vaccines, how do you think the implementation of distributing the vaccine and getting people to take it will play out?
LS: There are weekly conversations regarding how to distribute the vaccine and who should get it first. Clearly, they have to treat frontline workers first as they are the most at risk. Then the conversation is about who is most at risk for the virus aside from the frontline workers. People of color have a higher risk of getting sick from COVID-19 completely disproportionate to the population. The question raised asks if young children should be prioritized in getting the vaccine since they can be reservoirs of the virus and for their emotional and cognitive development must be allowed to return to school as soon as possible? There are still conversations going on around how to allocate the vaccine equally and I don’t think they have reached a complete conclusion other than the frontline workers will get it first. Who gets it next and how it rolls out is still under discussion.
MH: Is there worry that there will not be enough people willing to get the vaccine due to stigma?
LS: Yes, I think that is a very significant concern. I can personally tell you as a scientist that I think that vaccines and antibiotics have extended our lives dramatically. At the beginning of the 1900s, the average life span was about 40 years old due to people dying from common infectious diseases. The advantage of antibiotics and vaccines has extended our lifespan by double. I will not hesitate in getting a vaccine as soon as I can after it has been reviewed and approved by an independent, apolitical group of scientists.
MH: Are there any other major ethical topics that we missed that you would like to discuss?
LS: One critical vast ethical issue that we have not discussed is CRISPR technology. CRISPR technology is one of the most fraught technologies on the planet with the ability to do both good and bad. On the downside, scientists have found ways for example to change genes in entire populations of mice to render them infertile so that they cannot transmit Lyme disease or to eradicate entire populations of mosquitoes to prevent malaria or zika transmission or other mosquito borne diseases, of which there are many. What happens to the global ecosystem if these species are eradicated because they can no longer reproduce? The cat is out of the bag on this line of research, before a discussion on the ethics ever got started.
The first infants to have their genes in their germline modified have already been born in China. This means the germplasm (eggs and sperm) have been permanently altered and so these modifications will be transmittable to future generations. This is something that the scientific and civil community worldwide has historically completely forbidden. There are a lot more conversations surrounding ethics that need to take place in order for this technology to be broadly used. I’m afraid, it is already too late to regulate and control in a meaningful way from being used in ways that could be terribly detrimental to our planet and all its inhabitants, whether fauna, flora, microbes, or humans.
The Pursuit of a SARS-CoV-2 Vaccine: Lessons in Public Trust of Medical Institutions
By Jessica Lee, Biochemistry and Molecular Biology ‘21
Author’s Note: Alarmed by the fact that so many Americans are skeptical of receiving a COVID-19 vaccine, I wanted to write an article delving into the reasons why public trust in medical institutions has waned. I look to previous breaches of trust to propose public health messaging strategies for the rollout of the highly anticipated COVID-19 vaccine.
As of November 2020, approximately 63% of Americans say they would not be willing to immediately receive a COVID-19 vaccine—even if the vaccine was approved by the Food and Drug Administration (FDA) and free of cost [1]. Public willingness to receive a COVID-19 vaccine has rebounded since its all time low of 50% in September of 2020. The fluctuation in willingness to be vaccinated reflects how the public perceives undue influence on the vaccine development and regulation process. A successful vaccine distribution process will require broad public support to control the ongoing global pandemic.
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The human and economic consequences of the COVID-19 pandemic are staggering: over 350,000 people in the U.S. have died from COVID-19 and the unemployment rate remains high at 6.7% as compared to 3.5% in February 2020 [2, 3]. Given the devastating impacts of COVID-19 on Americans’ health and well-being, why are so many Americans skeptical of a vaccine with the potential to restore normalcy?
The history of American public and private biomedical institutions may provide useful context for Americans’ skepticism of a potential COVID-19 vaccine. The anti-vaccination movements, opioid crisis, and bumpy introduction of COVID-19 therapeutics have all contributed to waning trust in public health institutions. With the approval of Pfizer/BioNTech and Moderna vaccine candidates for the prevention of COVID-19, the biomedical community needs to foster trust by delivering correct and consistent messaging to the public as vaccines become available to the American public.
Trust in Biomedical Institutions
The modern anti-vaccination, or “anti-vax,” movement in the U.S. was sparked by Andrew Wakefield’s infamous paper published in The Lancet and perpetuated by outspoken celebrities, politicians, and social media groups [4]. Even though Wakefield’s claims about a causal relationship between the childhood measles, mumps, and rubella (MMR) vaccine and autism have since been thoroughly debunked by a scientific majority, the damage caused by his falsified research is evident as measles outbreaks continue to impact the U.S. Characterized by fantastical and conspiratorial thinking, the modern anti-vax movement has evolved to include a range of beliefs about vaccines. On social media platforms, misinformation about vaccines can include false safety concerns to conspiracies about social control.
However, there are also legitimate reasons to be skeptical of the pharmaceutical industry and its regulators. Mistakes driven by commercial interests have resulted in horrific public health crises. Motivated by profit, pharmaceutical companies misled the public about the safety of opioids, such as oxycontin, resulting in the liberal prescription of highly addictive and dangerous drugs. Opioid overdose is now one of the most common causes of preventable death in the U.S. [5]. Financial incentives can corrupt the scientific process, even corrupting leading medical experts.
Dr. Russell Portenoy, a pain specialist, received millions of dollars from the manufacturers of opioids while assuring the public that addiction risks were low [5]. When the addictive nature of opioids became evident, Portenoy defended his actions.
“My viewpoint is that I can have these relationships [and] they would benefit my research mission and to some extent, they can benefit my own pocketbook, without producing in me any tendency to engage in undue influence or misinformation,” said Portenoy [5].
In light of the unethical—and often illegal—behavior of pharmaceutical companies, the reaction of the American public is not entirely unreasonable. However, the waning trust in biomedical institutions is nonetheless a public health problem with clear consequences. In 2019, there were several outbreaks of measles among communities with low vaccination rates [6]. Over 1,200 cases were reported by the Center for Disease Control (CDC), which is the highest number of measles cases since 1992 [6]. It is important to highlight that overall measles vaccination rates are high throughout the country. However, outbreaks of deadly diseases can still occur when vaccination rates within a community dip below those needed for herd immunity. To eradicate a disease, outreach to fringe communities is necessary to ensure they buy into the vaccination process. Furthermore, vaccines must be made accessible to traditionally underserved communities. Within the context of the COVID-19 pandemic, this means that public health officials must reach out to those with anti-vaccination tendencies, ethnic minorities, and immigrant populations. Furthermore, the vaccine must be made widely accessible for the poorest citizens of all countries. Only then can COVID-19 be completely eradicated.
Number of Measles cases reported by year
Data from CDC.gov as of October 15, 2020
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The consequences of eroded trust in biomedical institutions are even more tangible as authorities in the U.S. attempt to control the COVID-19 pandemic. Confusing, conflicting messaging and policies on cloth mask usage has resulted in a partisan gap of 16 points between Republicans and Democrats on regular mask usage [7]. Even though current data and modeling demonstrate that masks reduce infections, some Americans continue to refuse to participate in this common-sense risk reduction practice [8].
The Credibility of the Food and Drug Administration (FDA)
There has also been widespread confusion on the development of COVID-19 therapeutics. The FDA has the authority to allow the use of unapproved drugs and medical products during national emergencies under an emergency use authorization (EUA). Many COVID-19 therapeutics such as Remdesivir, hydroxychloroquine, and convalescent plasma have been granted EUAs for use in specific populations, such as hospitalized patients [9]. Importantly, medical products that are granted EUAs are not granted full FDA approval. To obtain an EUA, it must be determined that the product meets three criteria: the product may be effective in diagnosing, treating, or preventing a serious disease or condition, the known and potential benefits outweigh the risks, and there are no available alternatives [9]. Many of the EUAs granted for COVID-19 treatment have stirred controversy within the biomedical community. For instance, the FDA’s decision to grant an EUA for the use of convalescent plasma in August resulted in dissent among biomedical institutions.
A National Institutes of Health (NIH) panel rebutted the FDA’s claims by issuing this statement: “There are insufficient data for the COVID-19 Treatment Guidelines Panel to recommend either for or against the use of COVID-19 convalescent plasma for the treatment of COVID-19” [10].
Other figures in the biomedical community such as Dr. Eric Topol, the director of the Scripps Research Translational Institute, criticized the head of the FDA, Dr. Stephen Hahn, for making hyperbolic statements on the safety and efficacy of convalescent plasma and for presenting misleading data to the public [11].
“So in order to get this straight, Dr. Hahn needs to also talk to the public and say that he erred and that there is no established evidence for survival advantage of convalescent plasma. That has to be determined through randomized trials that are ongoing,” said Topol on NPR’s All Things Considered [11].
The FDA also has played a controversial part in the development of hydroxychloroquine. The agency issued an EUA for hydroxychloroquine in March only to revoke the EUA in June after adverse cardiac events were reported [12]. Whether the FDA’s actions were influenced by political pressure, corporate pressure, or a desire to save lives, the controversy around COVID-19 therapeutics degrades public trust in the FDA as an institution.
Emergency Use Authorization for Vaccines to Prevent COVID-19
The discussion on therapeutic EUAs is important since the two currently approved COVID-19 vaccines were first approved through the intermediate step of an EUA. At time of publication, Moderna and Pfizer/BioNTech have successfully completed their phase three clinical trials for COVID-19 vaccines and received EUAs from the FDA [13]. Globally, approximately twenty other vaccine candidates are also in phase three clinical trials [13]. Each clinical trial has enrolled between 30,000 and 60,000 volunteers, half of which will receive the vaccine candidate and half of which will receive a placebo [13]. Approximately 160 infections of SARS-CoV-2 will be necessary to statistically determine the efficacy of each vaccine candidate. While only 160 infections might seem small in a clinical trial of 60,000, this number allows the FDA to determine if there is a statistical significance between the two arms of the clinical trial. Interim analyses may also be conducted at fewer infections by external data safety monitoring boards [14, 15]. Such data safety monitoring boards are independent of sponsors, regulators, and the scientists conducting the clinical trials. If the external board finds statistically significant results at an interim point, then the sponsors of the clinical trial may ask the FDA to review the vaccine for an EUA [14].
Published in a non-binding guidance document, the FDA outlines the criteria for potentially obtaining an EUA for a COVID-19 vaccine. Since this guidance document is non-binding, the FDA may modify the EUA process moving forward. If a sponsor seeks an EUA at an interim analysis of a phase three clinical trial, then they must demonstrate at least 50% efficacy, have a median follow-up duration of at least two months after the administration of the last dose, and safety data that would allow the FDA to make a favorable risk-benefit analysis [16]. Furthermore, the sponsor must provide sufficient data demonstrating the ability to consistently manufacture the vaccine [16]. If the FDA believes the criteria are met for an EUA, then the vaccine candidate may be administered to certain at-risk populations while the full-approval process continues. At the time of publication, both Pfizer and Moderna have produced data from their phase three clinical trials indicating their vaccines may be over 90% effective—far surpassing the 50% efficacy threshold set by the FDA [13].
Developing and Maintaining Public Trust
The COVID-19 vaccine trials are safeguarded in many ways. The scientists at the FDA have approved the phase three clinical trial protocols and monitored phase one and two clinical trials for safety and efficacy. The oversight safety boards have watched for unexplained adverse events and paused the AstraZeneca trial when unexplained neurological symptoms presented in one participant [14]. Peer reviewers have analyzed and criticized the data and conclusions generated from phase one and two clinical trials. Furthermore, influential members of the biomedical community have spoken out when they believe mistakes have been made. Evidently, there are safety measures in place to protect the public from a dangerous or ineffective vaccine. However, safety measures are not perfect. When the FDA allowed the use of hydroxychloroquine and then revoked its EUA, the FDA weakened its authority with the general public. Even the appearance of political and commercial influence on the scientific process may elicit skepticism from the public.
How can the biomedical community increase the public’s willingness to get the COVID-19 vaccine? Certainly, consistent messaging from figures of authority is important. Furthermore, the biomedical community must continue to hold regulatory agencies, corporations, and politicians responsible for their rhetoric. There must be political, legal, or economic consequences for misleading the public and degrading trust in medical institutions. Economic consequences—for example—might range from lawsuits to executives being debarred from working in the pharmaceutical industry.
Biomedical professionals have advocated for widespread outreach to many different types of communities [15]. Social media campaigns can be effective in rapidly disseminating information by engaging users to add their own input. However, social media may also hinder outreach as demonstrated by the uncontrolled spread of misinformation by anti-vaccination groups on platforms such as Facebook [17]. Viral posts containing misinformation can seed public distrust in medical institutions. Still, polling indicates that Americans overwhelmingly trust medical professionals over industry leaders or politicians for information about vaccines [18].
[18]
Utilizing this trust would mean elevating medical scientists as the voice communicating the state of a COVID-19 vaccine rather than relying on politicians, the news media, or industry leaders. However, it is important to communicate scientific consensus rather than relying on the voices of individual biomedical professionals. Individuals can make genuine mistakes, have differing opinions, or be corrupted; thus, it is essential that public health messaging is centered around scientific consensus.
The effectiveness of a COVID-19 vaccine on a population scale will depend on the percent of people willing to get the vaccine. To end the COVID-19 pandemic, it’s likely that most people will need to be vaccinated. To accomplish this, the biomedical community will need to work with the public to foster open and honest communication, understanding the public has relevant concerns about the influence of politics and commerce on the scientific process. By learning from previous anti-vax movements, public health professionals must counter the spread of misinformation with compelling, fact-based messaging. Ultimately, the public health community must regain the trust of the American public and appeal to Americans’ civic duty. The act of taking a vaccine is a social contract; as Dr. Topol says, “I take the vaccine to help you, not just me” [15]. The COVID-19 pandemic is one of the largest public health crises in modern times and it will require good science and good communication to solve.
References
[1] Brenan M. “Willingness to Get COVID-19 Vaccine Ticks Up to 63% in U.S.” Gallup, December, 2020.
[2] “CDC COVID Data Tracker.” Centers for Disease Control and Prevention, January 6, 2021.
[3] “Employment Situation Summary.” U.S. Bureau of Labor Statistics, December, 4, 2020.
[4] Hussain A, Ali S, Ahmed M, Hussain S. “The Anti-vaccination Movement: A Regression in Modern Medicine.” Cureus, July 2018. doi: 10.7759/cureus.2919.
[5] Gale AH. “Drug Company Compensated Physicians Role in Causing America’s Deadly Opioid Epidemic: When Will We Learn?” Mo Med, July 2016.
[6] “Measles Cases and Outbreaks.” Center for Disease Control, November 2020.
[7] Kramer S. “More Americans say they are regularly wearing masks in stores and other businesses.” Pew Research Center, August 2020.
[8] Zhang K, Vliches TN, Tariq M, Galvani AP, Moghadas SM. “The impact of mask-wearing and shelter-in-place on COVID-19 outbreaks in the United States.” International Journal of Infectious Diseases, December 2020. doi: 10.1016/j.ijid.2020.10.002.
[9] “Frequently Asked Questions for Veklury (remdesivir).” U.S. Food and Drug Administration, October 2020.
[10] COVID-19 Treatment Guidelines Panel. “Coronavirus Disease 2019 (COVID-19) Treatment Guidelines.” National Institutes of Health, Accessed November 2020.
[11] “Researcher Criticizes FDA’s Exaggeration Of Plasma’s Efficacy In COVID-19 Treatment.” All Things Considered. NPR, August 2020.
[12] “Coronavirus (COVID-19) Update: FDA Revokes Emergency Use Authorization for Chloroquine and Hydroxychloroquine.” U.S. Food and Drug Administration, June 2020.
[13] Corum J, Wee S, Zimmer C. “ Coronavirus Vaccine Tracker.” The New York Times, January 2021.
[14] Duke Science & Society. “Coronavirus Conversations: On the Ground – Inside the COVID-19 Vaccine Trials.” Online video clip. Youtube, 6 November 2020.
[15] Duke Science & Society. “Coronavirus Conversations: Emergency Use Authorizations, Public Trust, and Vaccines.” Online video clip. Youtube, 7 October 2020.
[16] “Emergency Use Authorization for Vaccines to Prevent COVID-19; Guidance for Industry.” U.S. Food and Drug Administration, October 2020.
[17] Johnson NF, Velásquez N, Restrepo NJ, Leahy R, Gabriel N, Oud SE, Zheng M, Manrique P, Wuchty S, Yonatan L. “The online competition between pro- and anti-vaccination views.” Nature, May 2020.
[18] Funk C, Kennedy B, Hefferon M. “Vast Majority of Americans Say Benefits of Childhood Vaccines Outweigh Risks.” Pew Research Center, February 2020.
Engineering Hepatitis Virus-like Particles for Oral Vaccine Delivery
By David Ivanov, Biochemistry ’15
Oral vaccines are known to be a convenient and effective method for treatment or prevention of diseases caused by pathogenic microorganisms. The difficulty of developing such vaccines is due to the often inhospitable environment of the stomach and intestinal tract because of low pH, or acidity, as well as enzymes that can digest or destroy biological molecules. Using a virus-like particle to deliver the vaccine is an advantageous method for getting around these and other barriers in the host organism.
A virus-like particle, or VLP, is a biological particle that resembles a virus, but contains no genetic information and thus cannot infect host cells. VLP’s can be formed by inserting and expressing just the genes for creating the viral capsid, which is a shell made up of protein subunits that protects the infectious genetic information in wild-type, or normal, viruses. The expressed capsid proteins can then self-assemble into the VLP. The capsid also has domains, or structural areas, that are responsible for recognizing suitable host cells to infect and inserting the viral genome.